Reach assembly with improved operator visibility for a materials handling vehicle

Abstract

A materials handling vehicle includes a power unit, a mast assembly coupled to the power unit, and a reach assembly coupled for vertical movement on the mast assembly. The mast assembly includes first, second, and third weldments, wherein the first weldment is fixed to the power unit, the second weldment is movable with respect to the first weldment, and the third weldment is movable with respect to the first and second weldments. The reach assembly includes an extension/retraction mechanism for effecting horizontal movement of the reach assembly relative to the mast assembly. Components of the vehicle have been redesigned and/or rearranged to improve operator visibility.

What is claimed is: 
     
         1 . A reach assembly for use on a materials handling vehicle including an operator's compartment, the reach assembly comprising:
 a mast carriage assembly coupled for vertical movement on a mast assembly of the materials handling vehicle;   a fork carriage assembly comprising a pair of forks; and   an extension/retraction mechanism for effecting longitudinal movement of the fork carriage assembly relative to the mast carriage assembly, the extension/retraction mechanism comprising:
 a pair of spaced apart inner arms coupled between the mast carriage assembly and the fork carriage assembly; 
 a pair of spaced apart outer arms laterally outward from the respective inner arms and coupled between the mast carriage assembly and the fork carriage assembly, the outer arms being pivotably coupled to the inner arms to enable the longitudinal movement of the fork carriage assembly relative to the mast carriage assembly; 
 an upper coupling member extending laterally between the inner arms; 
 an intermediate coupling member positioned beneath the upper coupling member and extending laterally between the inner arms; 
 a lower coupling member positioned beneath the intermediate coupling member and extending laterally between the inner arms, the coupling members providing structural rigidity for the extension/retraction mechanism; and 
 first and second operator viewing windows extending longitudinally through the reach assembly when the extension/retraction mechanism is in a retracted position, wherein the first operator viewing window is defined between the upper and intermediate coupling members and the second operator viewing window is vertically spaced apart from the first operator viewing window and is defined between the intermediate and lower coupling members, the operator viewing windows having vertical dimensions that are larger than a vertical height of at least one of the coupling members. 
   
     
     
         2 . The reach assembly as set out in  claim 1 , wherein the operator viewing windows have vertical dimensions that are larger than each of the coupling members. 
     
     
         3 . The reach assembly as set out in  claim 1 , wherein the fork carriage assembly further comprises a tilt and side shift bar used for tilt and side shift functions. 
     
     
         4 . The reach assembly as set out in  claim 3 , wherein the tilt and side shift bar is generally vertically in plane with the intermediate coupling member when the extension/retraction mechanism is in a fully retracted position. 
     
     
         5 . The reach assembly as set out in  claim 3 , wherein the fork carriage assembly further comprises a frame comprising a hanger bar and a lower member. 
     
     
         6 . The reach assembly as set out in  claim 5 , wherein the tilt and side shift bar, the hanger bar of the frame, and the intermediate coupling member each intersect a common horizontal plane so as to be longitudinally stacked with one another when the extension/retraction mechanism is in a fully retracted position. 
     
     
         7 . The reach assembly as set out in  claim 5 , wherein the lower member of the frame and the lower coupling member each intersect a common horizontal plane so as to be longitudinally stacked with one another when the extension/retraction mechanism is in a fully retracted position. 
     
     
         8 . The reach assembly as set out in  claim 1 , wherein the fork carriage assembly further comprises an upper cross brace that is located between the upper and intermediate coupling members when the extension/retraction mechanism is in a fully retracted position, the upper cross brace dividing the first operator viewing window into upper and lower first operator viewing window portions. 
     
     
         9 . The reach assembly as set out in  claim 8 , wherein the first operator viewing window portions have vertical dimensions that are larger than at least one of the coupling members. 
     
     
         10 . The reach assembly as set out in  claim 1 , further comprising a piston cylinder assembly for extending and retracting the extension/retraction mechanism to effect longitudinal movement of the fork carriage assembly relative to the mast carriage assembly. 
     
     
         11 . The reach assembly as set out in  claim 10 , wherein the piston cylinder assembly comprises a single cylinder that is laterally offset with respect to a longitudinal centerline of the materials handling vehicle so as to allow improved visibility through the first and second operator viewing windows. 
     
     
         12 . A reach assembly for use on a materials handling vehicle including an operator's compartment, the reach assembly comprising:
 a mast carriage assembly coupled for vertical movement on a mast assembly of the materials handling vehicle;   a fork carriage assembly comprising a frame that supports a pair of forks;   a tilting mechanism for effecting tilting movement of the frame relative to the mast carriage assembly; and   a pair of tilt limiters that limit the amount of tilting movement that the frame can undergo relative to the mast carriage assembly, wherein the tilt limiters are spaced apart from one another in a lateral direction and are laterally offset with respect to a longitudinal centerline of the materials handling vehicle so as to allow improved visibility from the operator's compartment through an operator viewing space defined between the tilt limiters.   
     
     
         13 . The reach assembly as set out in  claim 12 , wherein the tilt limiters each have a lower abutment surface for contacting an upper surface of a lower member of the frame as the frame is being tilted to define an uppermost tilt position for the frame. 
     
     
         14 . The reach assembly as set out in  claim 12 , wherein the tilt limiters are affixed to vertical members of the fork carriage assembly and extend from the vertical members in a longitudinal direction toward the forks. 
     
     
         15 . The reach assembly as set out in  claim 12 , wherein a lateral distance of the operator viewing space between the tilt limiters is at least about 150 mm. 
     
     
         16 . The reach assembly as set out in  claim 12 , wherein a lateral distance of the operator viewing space between the tilt limiters is at least about 5 times a lateral width of each of the tilt limiters. 
     
     
         17 . A reach assembly for use on a materials handling vehicle including an operator's compartment, the reach assembly comprising:
 a mast carriage assembly coupled for vertical movement on a mast assembly of the materials handling vehicle, the mast carriage assembly including a rear box weldment comprising:
 an upper support plate; 
 a lower support plate vertically spaced from the upper support plate; and 
 a pair of side plates extending from the upper support plate to the lower support plate, the side plates each comprising:
 an intermediate member having first and second side faces that face in a lateral direction of the materials handling vehicle; 
 a rear member extending laterally inwardly from a rear end of the intermediate member, located proximal to the operator's compartment, and having first and second side faces that face in a longitudinal direction of the materials handling vehicle; and 
 a front member extending laterally outwardly from a front end of the intermediate member, located distal to the operator's compartment, and having first and second side faces that face in the longitudinal direction of the materials handling vehicle; 
 wherein the front, intermediate, and rear members of the side plates provide each of the side plates with a cross section having a Z-shape when viewed from above; and 
 
   a fork carriage assembly comprising a pair of forks and being moveable longitudinally with respect to the mast carriage assembly.   
     
     
         18 . The reach assembly as set out in  claim 17 , wherein a front portion of an upper surface of the upper support plate of the rear box weldment is chamfered. 
     
     
         19 . The reach assembly as set out in  claim 17 , wherein the intermediate member of each of the first and second side plates has a larger longitudinal dimension than a lateral dimension of the front and rear members of each of the first and second side plates.